Tolerance to intraoral biofilms and their effectiveness in improving mouth dryness and modifying oral microbiota in patients with primary Sjögren's syndrome: "Predelfi study".

Introduction: Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease characterized by exocrine gland dysfunction. No therapeutic strategy is sufficient on its own for the management of dry mouth and therapeutic innovations are required. Methods: This Predelfi study was a single-center, prospective, comparative, randomized, double-blind, cross-over controlled study with the primary objective of assessing the tolerance to and effectiveness of two adhesive biofilms (containing prebiotics and, sodium alginate, respectively) in patients with pSS and hyposialia (#NCT04206826 in ClinicalTrials.gov). Secondary objectives were to obtain initial data regarding the clinical effectiveness of such biofilms in the improvement of signs and symptoms related to dry mouth and potential changes in the oral microbiota. Ten pSS patients with pSS were included (9 females and 1 male) with a mean age of 58.1 ± 14.0 years. Results and discussion: Tolerance to the prebiotic and sodium alginate biofilms was assessed by the patients (visual analog scale [VAS] score 66.7 and 87.6, respectively) and the practitioner (90 and 100, respectively). The absolute changes in the VAS scores at the start and end of each treatment period highlighted an improvement in mouth dryness for the sodium alginate versus the prebiotic biofilm. The VAS scores for other parameters (mouth burning sensation; taste alteration; chewing; swallowing and speech difficulties) remained globally comparable between the two groups. Unstimulated salivary flow showed no changes regardless of the biofilm used. Regarding the oral microbiota, the sodium alginate biofilm increased the abundance of the Treponema genus, whereas the use of the prebiotic biofilm as the first treatment increased the abundance of the genera Veillonella and Prevotella. Nevertheless, the prebiotic biofilm appeared to stimulate "milder" genera with regard to periodontal infections. Furthermore, pre-treatment with the prebiotic biofilm prevented the emergence of the Treponema genus induced by subsequent treatment with the sodium alginate biofilm, suggesting a potential protective effect.

Alcohol consumption, alcohol expectancies, and drinking contexts in young Argentinean college students before and during the COVID-19 pandemic: a one-year follow-up study.

Background: The COVID-19 pandemic and lockdowns are known to affect alcohol consumption. This study examines drinking expectancies and contexts upon alcohol consumption of Argentinean students.Objectives: To assess within-person changes in alcohol consumption in Argentinean college students (aged 18-24), from August 2019 with a one-year follow-up during the COVID-19 lockdown, considering alcohol expectancies, drinking contexts, and main socio-demographic variables. To validate the stability of these predictors, we discuss the effects on the alcohol consumption across dependent and independent measures.Methods: We assessed one longitudinal (N = 300, 70% female) and one cross-sectional (N = 165, 78% female) sample via online surveys and applied multilevel analysis and regressions, respectively.Results: Alcohol consumption significantly increased during lockdown compared to one-year before (mean: 6.91 and 8.26 alcohol units, correspondingly). In the longitudinal sample, social facilitation (medium effect sizes [ES]: 0.21, 0.22) and parental presence (medium ES: 0.12, 0.21) significantly and stable (through time) predicted increasing effects on consumption. In the cross-sectional sample, stress control (high ES: 0.78) and parental presence (high ES: 0.42) were associated with higher consumption during lockdown.Conclusion: College students increased their alcohol consumption during lockdown, suggesting that restrictive sanitary measures may negatively affect consumption. Literature is not conclusive as both decreases and increases in alcohol consumption in students from developed countries were reported. Before and during COVID-19 lockdown, parental presence is a stable predictor of increased alcohol consumption, though unusual according to the literature. Health policies aimed at modifying the behavior of parents who promote/share alcohol consumption with their offspring may help reduce drinking in college students.

A longitudinal study on depression and anxiety in college students during the first 106-days of the lengthy Argentinean quarantine for the COVID-19 pandemic.

BACKGROUND: The Argentinean quarantine is among the strictest and longest quarantines in the world. To determine if a worsening pattern on mental health would emerge with a prolonged quarantine duration, a longitudinal analysis pertaining to the lengthy mandatory Argentinean quarantine was conducted. AIM: To examine depression and anxiety changes in college students, as a function of quarantine duration, demographic and health-related factors, during successive time cuts of the lengthy mandatory quarantine in Argentina. METHODS: We used a longitudinal design, N = 1492 college students. For the first measurement, successive samplings were carried out across quarantine sub-periods of up to 106-days duration. The follow-up was one month later. RESULTS: Particularly women, young, and having a history of mental disorder and suicidal behavior, were more depressed and anxious under mandatory restrictive quarantine conditions. Repeated measures of both depression and anxiety scores remained constantly high during the more restrictive quarantine sub-periods of up to 13 and 53-days duration, and decreased during the less restrictive quarantine sub-period of up to 106-days duration, but with small effect sizes (0.10-0.08). CONCLUSIONS: Restrictive quarantine has negative effects on mental health outcomes. Partial spontaneous remissions of depression and anxiety symptoms may be expected with further quarantine relaxations.

Microbiota in Periodontitis: Advances in the Omic Era.

The complexity of the oral microbiome continues to astound researchers even with the advancement of multi-disciplinary strategies being used to study these microorganisms in relation to the human body. There is extensive literature available that explains how oral bacterial communities exist within the biofilm and maintains a balance with the host immune system, but when this balance is tipped disease can occur. The purpose of this review is to highlight the subgingival microbial compositions during health and periodontal disease using next generation sequencing techniques, as well as determining the types of functional activities that partake during these states. The subgingival microbiota is a fluid structure that can adapt accordingly to the environment and the identification of signature biomarkers may aid in the assessment of risk and disease severity in an individual to complement clinical diagnosis in the future.

Levels and predictors of depression, anxiety, and suicidal risk during COVID-19 pandemic in Argentina: the impacts of quarantine extensions on mental health state.

This research is aimed to: analyze differences in mental health state (MHS) indicators (depression, state-anxiety, trait-anxiety, and suicidal risk), during three quarantine sub-periods (starting since the first quarantine extension); assess multiple relationships between each MHS indicator and potentially affecting factors. We used a cross-sectional design with a convenience sample including 1100 participants. Data were collected online. Depression revealed a worsening pattern as quarantine sub-periods went by. Anxiety (both state and trait), just like suicidal risk, partially follow such a pattern, with mean scores increasing from the first to the second/third quarantine extensions, but then maintaining to the fourth extension. Predictors having protective effects on almost all the MHS indicators were: availability of current economic income (except for state-anxiety, without significant effect) and absence of suicide attempt history. Conversely, sex (woman), younger age, and mental disorder history had an increasing risk effect on all the MHS indicators. Overall, our findings indicate that quarantine have negative mental health impacts and that quarantine duration is a relevant aspect to be taken into account when measuring such an impact. More attention needs to be paid to vulnerable groups such as the young, women, and people with history of mental disorder.

Porphyromonas gingivalis outside the oral cavity.

Porphyromonas gingivalis, a Gram-negative anaerobic bacillus present in periodontal disease, is considered one of the major pathogens in periodontitis. A literature search for English original studies, case series and review articles published up to December 2019 was performed using the MEDLINE, PubMed and GoogleScholar databases, with the search terms "Porphyromonas gingivalis" AND the potentially associated condition or systemic disease Abstracts and full text articles were used to make a review of published research literature on P. gingivalis outside the oral cavity. The main points of interest of this narrative review were: (i) a potential direct action of the bacterium and not the systemic effects of the inflammatory acute-phase response induced by the periodontitis, (ii) the presence of the bacterium (viable or not) in the organ, or (iii) the presence of its virulence factors. Virulence factors (gingipains, capsule, fimbriae, hemagglutinins, lipopolysaccharide, hemolysin, iron uptake transporters, toxic outer membrane blebs/vesicles, and DNA) associated with P. gingivalis can deregulate certain functions in humans, particularly host immune systems, and cause various local and systemic pathologies. The most recent studies linking P. gingivalis to systemic diseases were discussed, remembering particularly the molecular mechanisms involved in different infections, including cerebral, cardiovascular, pulmonary, bone, digestive and peri-natal infections. Recent involvement of P. gingivalis in neurological diseases has been demonstrated. P. gingivalis modulates cellular homeostasis and increases markers of inflammation. It is also a factor in the oxidative stress involved in beta-amyloid production.

A Longitudinal Study on the Changes in Mental Health of Healthcare Workers during the COVID-19 Pandemic.

Objective: This study examines Argentinean health care workers in order to 1) test self-perceived job performance levels and the presence of psychological symptoms compatible with common mental disorders, and 2) examine within-person changes in general discomfort and psychological distress, adjusting for demographic factors, region, and health-related factors during two time points of the COVID-19 pandemic.Method: This longitudinal study comprised 305 healthcare workers who completed a survey at two time points approximately 4 months apart. We used the General Health Questionnaire and the Kessler Psychological Distress Scale to measure mental health outcomes. To address the first aim we calculated differences (Student's t test for paired samples) and correlations (Pearson's r coefficient). To address the second aim we used fixed effects model by means of a multilevel approach, a linear model that considers dependency in the data.Results: Self-perceived job performance deteriorated across time. From the first measurement to the four-month follow-up, more health care workers presented common mental disorders (40% vs 45.57%), depression, and/or anxiety (52.46% vs 62.62%). A meaningful worsening of mental health was observed in healthcare workers who expressed concern about being infected with COVID-19, whether asymptomatic (greater general discomfort and psychological distress) or symptomatic (greater general discomfort). Likewise, there were significant interactions between a history of mental disorder and concern about COVID-19 infection.Conclusions: Among healthcare workers, the uncertainty about the COVID-19 infection may have larger negative mental health impacts than actually being infected.

Changes in Healthcare Workers' Anxiety During Two Time Points of the COVID-19 Pandemic: Evidence From a Longitudinal Study.

Evidence on the within-person changes of healthcare workers' mental health across waves of COVID-19 cases during this pandemic is absent. The aim of this study is to examine the within-person changes of anxiety in Argentinean healthcare workers, adjusting for main demographic factors, region of residence, mental disorder history, and COVID-19 contagion, during the COVID-19 pandemic. A longitudinal web survey (N = 305) was conducted during two time points of the pandemic, one of which was an infection peak. Anxiety significantly increased across time. However, there were significant interaction effects modulating anxiety levels. The largest anxiety increases occurred in healthcare workers who were not sure if they had contracted COVID-19 while symptomatic. Irrespective of the time point, anxiety was the highest in healthcare workers from a region inside the country who were not sure if they had contracted COVID-19, either asymptomatic or symptomatic. An interaction effect between the mental disorder history and the COVID-19 contagion suggested that the anxiety outcomes were mainly due to the concern about the COVID-19 contagion, rather than due to pre-existing mental health vulnerabilities. Regardless of the starting point in anxiety levels, an increasing anxiety outcome may be expected among healthcare workers as the pandemic progresses. The uncertainty regarding COVID-19 contagion is a preventable and modifiable interacting factor to produce the worst anxiety outcomes among healthcare workers.

Suicidal risk and impulsivity-related traits among young Argentinean college students during a quarantine of up to 103-day duration: Longitudinal evidence from the COVID-19 pandemic.

AIM: This study aimed to examine longitudinal changes on suicidal risk levels, adjusting for impulsivity-related traits, quarantine duration, main demographic factors, mental disorder history, and loneliness, in young Argentinean college students with (ideation; attempt) and without suicidal behavior history, during a quarantine of up to 103-day duration of the COVID-19 pandemic. METHODS: A longitudinal design with two-repeated measures was used (N = 1202). Follow-up was a month later from the first measurement. Three groups were analyzed: with suicidal ideation history, with suicide attempt history, and without suicidal behavior history. RESULTS: Percentages of college students with high or moderate suicidal risk were alarming (accumulated: 62.23% first measurement, 57.65% second measurement). Multilevel analysis on the three groups showed that suicidal risk diminished from the first measurement to the follow-up, having mental disorder history predicted higher suicidal risk, and negative urgency had the largest increasing effects on suicidal risk which persisted over time. CONCLUSIONS: Suicidal risk widely affects college students during lengthy quarantines of the COVID-19 pandemic and it should be tracked in those having pre-existing vulnerabilities, but also in those without. Education on managing negative emotions may help decrease suicide risk in college students during the COVID-19 pandemic.

Mental Health Impacts in Argentinean College Students During COVID-19 Quarantine.

Background: We aimed to: (1) analyze differences in both general (in terms of psychological well-being/discomfort, social functioning and coping, and psychological distress) and specific (depression, trait-anxiety, negative alcohol-related consequences, and suicidal risk) mental health state (MHS) in college students, residing in four different Argentinean regions (center, north, south, and the most populated) exposed to different spread-rates of the COVID-19; (2) analyze between-group differences in both general and specific MHS indicators at four quarantine sub-periods (twice prior, and twice following the first quarantine extension). Methods: We used a cross-sectional design with a convenience sample including 2,687 college students. Data was collected online during the Argentinean quarantine. We calculated one-way between-groups ANOVA with Tukey's post hoc test. Results: Regionally, the center and the most populated area differed in psychological well-being/discomfort and negative alcohol-related consequences, but not in the remaining MHS indicators. According to the quarantine sub-periods, there were differences in psychological well-being/discomfort, social functioning and coping, psychological distress, and negative alcohol-related consequences. Negative alcohol-related consequences were the only MHS indicator improving over time. For all of the remaining MHS indicators, we found a similar deterioration pattern in the course of time, with mean scores decreasing from the first to the 2nd week of the quarantine pre-extensions, then increasing toward the 1st week of the quarantine post-extension (with some MHS indicators reaching mean scores worse than the start), and then continued to increase. Conclusion: A worsened mean MHS during quarantine suggests that quarantine and its extensions contribute to negative mental health impacts.

Longitudinal evidence on mental health changes of college students with and without mental disorder background during the Argentina's lengthy mandatory quarantine.

This study examined the changes in the mental health state of college students with and without mental disorder background, during successive time cuts of the Argentina's lengthy mandatory quarantine, while adjusting for quarantine duration, sex, age, suicidal behavior history, loneliness, and region of residence. We used a longitudinal design (N = 1615, 26% with mental disorder history). Successive samplings were performed from three days before quarantine start and across quarantine phases of up to 103-days duration. Follow-up was one month later. Sex (woman) and age (younger) were significant predictors of worse mental health only in college students without mental disorder background. Having any suicidal behavior background significantly predicted worse mental health in college students both with and without mental disorder history. Loneliness and region of residence were not statistically significant. In the between-groups comparisons, college students having mental disorder background had worse mental health than those without such a background. However, in the within-subject comparisons, no statistically significant changes occurred across time in the mental health of college students having mental disorder history. Conversely, significant changes occurred in those without such a background, but only when the interaction between time and quarantine duration was considered. Worsening mental health occurred during the most heavily restrictive quarantine phases, while some of the remissions occurred during the longest, but less restrictive ones.

Oral dysbiosis induced by Porphyromonas gingivalis is strain-dependent in mice.

Background: Porphyromonas gingivalis strain W83, one of the most widely investigated, is considered virulent in the context of periodontitis. The recently isolated P. gingivalis TDC60 has been reported to be highly pathogenic, although it has not yet been investigated in a mouse periodontitis model by oral gavage. Aim: Our aim was to compare the virulence of both strains by evaluating their impact on alveolar bone loss and the composition of oral microbiota. Methods: We inoculated by oral gavage C57BL/6 mice with either one of the two P. gingivalis strains and compared to a sham-treated group, without antibiotics pre-treatment. The mandibular alveolar bone of treated mice and controls were assessed, one month after the final inoculation, by microCT measurements. Moreover, at this time, we characterized their oral microbiota by 16S rRNA gene sequencing. Results: While P. gingivalis W83 successfully initiated periodontitis, TDC60-treated mice only experienced moderate lesions. Furthermore, only W83-treated mice exhibited a specific distinct microbiota, with significantly lower richness and evenness than other samples, and decreased proportions of taxa usually found in healthy individuals. Conclusion: This association between alveolar bone loss and a major persistent shift of the oral microbiota gives insights into virulence discrepancies among these bacterial strains.

Altitude and latitude variations in trait-impulsivity, depression, anxiety, suicidal risk, and negative alcohol-related consequences in Argentinean adolescents.

The aims of this research were threefold: 1) to analyze mental health state both general (GMHS, i.e., self-perceived health and psychological distress) and specific (SMHS; i.e., depression, trait-anxiety, negative alcohol-related consequences, and suicidal risk), and impulsivity-related traits (i.e., negative urgency, positive urgency, [lack of] perseverance, [lack of] premeditation, and sensation seeking) in a sample of Argentinean adolescent college students, in function of sex (women, men) and three different altitude-latitude regions (high-north, middle-center, low-south), for identifying common and specific features; 2) to analyze relationships between impulsivity-related traits and indicators of GMHS and SMHS, in the entire sample and in each altitude-latitude region, for understanding the importance of impulsivity-related traits in these forms of mental disorders; and 3) to analyze bivariate relationships between depression, trait-anxiety, negative alcohol-related consequences, and suicidal risk, in the entire sample and considering the three altitude-latitude regions, for testing two-disorder comorbidities. Scores on impulsivity-related traits differed by sex and by altitude-latitude region. GMHS and SMHS differed by sex but not by altitude-latitude region. Several relationships were found between impulsivity-related traits, GMHS, and SMHS as well as between indicators of SMHS. Some of these relationships were dependent on altitude-latitude regions, and implications of these findings were discussed.

Waste into rivers: a residual issue? The case of the UNESCO's site of the Quebrada De Humahuaca, NW Argentina.

The Quebrada de Humahuaca in North West Argentina is a world heritage site listed by the UNESCO since 2003. As pollution is increasing dramatically, a pluridisciplinary, annual-long survey was conducted along the valley to determine dominant patterns in waste management and water quality. Along with the habit of discarding waste into the river, urbanizations have been identified as having a deep influence on the river water quality: iron together with maximum peaks of nitrite and nitrate are related with the anthropogenic activity at Humahuaca, whereas the concentrations of arsenic increase from north to south, with maximum peaks of up to 13.50 and 14.50 µg L-1 measured during the rainy season at Maimará and Volcán, respectively. In this underdeveloped region, economic struggles and waste management customs revealed as major factors causing the environmental degradation. The inclusion in the UNESCO's sites list was insufficient in preserving this world heritage site. The approach discussed in this article suggests a straightforward analytical measurement of the river hydrochemical properties during the rainy season in arid/semi-arid regions with monsoonal regime, to assess the effects of waste dumping along watercourses. In addition to scientific evaluations, both public acceptance and the establishment of proper waste management infrastructure are fundamental to ensuring the preservation of human and environmental health.

General Mental Health State Indicators in Argentinean Women During Quarantine of up to 80-Day Duration for COVID-19 Pandemic.

Introduction: Argentinean quarantine during the COVID-19 pandemic is one of the most long-lasting worldwide. We focused on the first 80-days of this quarantine on Argentinean women. Our aims were to analyze differences in general mental health state (MHS) indicators, by the (1) sites of residence with different prevalence of COVID-19 cases, and (2) quarantine duration; (3) to assess multiple relationships between each general MHS indicator and potentially affecting factors. Methods: We used a cross-sectional design with convenience successive sampling (N = 5,013). The online survey included a socio-demographic questionnaire (elaborated ad hoc) with standardized and validated self-reported questionnaires (General Health Questionnaire, Kessler Psychological Distress Scale) measuring the MHS indicators: self-perceived health, psychological discomfort, social functioning and coping, and psychological distress. Results: Worse self-perceived health and higher psychological discomfort affected significantly more women residing in sites with high prevalence of COVID-19 cases, compared to those residing in sites with intermediate prevalence, but effect sizes were small. Mean scores of all general MHS indicators were significantly worse for longer quarantine sub-periods (up to 53, 68, and 80-day duration) than for shorter sub-periods (up to seven, 13, and 25-day duration). Being a younger age, having mental disorder history, and longer quarantine durations were associated to worsening MHS, while the lack of previous suicide attempt has a protective effect. Discussion: Our findings show that a worse MHS during quarantine may not be attributed to the objective risk of contagion (measured greater or less), and under quarantine, women MHS-as indicated by group central tendency measures-got worse as time went by. This strongly suggests that special attention needs to be paid to younger women and to women with history of mental disorder. Along with physical health, mental health must be a priority for the Government during and after quarantine and the COVID-19 pandemic.

Lithium and Boron in Calcified Tissues of Vicuna and Their Relation to Chronic Exposure by Water Ingestion in The Andean Lithium Triangle.

Vicuna is a wild, endangered species of Andean camelid living in the hyperarid Andean plateau. In the central part of the plateau, the Lithium Triangle defines a zone with lithium-rich salt pans. Brine pools naturally form within the salt pans, and the adaptation strategy of vicuna consists of drinking from brine pools. Together with reporting the first chemical data on vicuna bones and teeth, we analyzed lithium, boron, and arsenic in water and brines, with the aim of assessing their relation to chronic exposure by water ingestion. We collected and analyzed bones of vicuna specimens lying in an Andean salt pan, together with brine and water samples. Brine and water samples are highly saline and contain large amounts of lithium, boron, and arsenic. Lithium (13.50-40 mg kg-1 ) and boron (40-46.80 mg kg-1 ), but not arsenic, were found in the vicuna bones and teeth. Based on our results and on previously reported data on human tissues in the Andes, we conducted statistical assessments of the relationships between lithium and boron in body tissues and water samples, and discuss their environmental significance in the context of the Lithium Triangle. Environ Toxicol Chem 2019;39:200-209. © 2019 SETAC.

Increased transferrin saturation is associated with subgingival microbiota dysbiosis and severe periodontitis in genetic haemochromatosis.

Genetic haemochromatosis (GH) is responsible for iron overload. Increased transferrin saturation (TSAT) has been associated with severe periodontitis, which is a chronic inflammatory disease affecting tissues surrounding the teeth and is related to dysbiosis of the subgingival microbiota. Because iron is essential for bacterial pathogens, alterations in iron homeostasis can drive dysbiosis. To unravel the relationships between serum iron biomarkers and the subgingival microbiota, we analysed samples from 66 GH patients. The co-occurrence analysis of the microbiota showed very different patterns according to TSAT. Healthy and periopathogenic bacterial clusters were found to compete in patients with normal TSAT (≤45%). However, significant correlations were found between TSAT and the proportions of Porphyromonas and Treponema, which are two genera that contain well-known periopathogenic species. In patients with high TSAT, the bacterial clusters exhibited no mutual exclusion. Increased iron bioavailability worsened periodontitis and promoted periopathogenic bacteria, such as Treponema. The radical changes in host-bacteria relationships and bacterial co-occurrence patterns according to the TSAT level also suggested a shift in the bacterial iron supply from transferrin to NTBI when TSAT exceeded 45%. Taken together, these results indicate that iron bioavailability in biological fluids is part of the equilibrium between the host and its microbiota.

Signature of Microbial Dysbiosis in Periodontitis.

Periodontitis is driven by disproportionate host inflammatory immune responses induced by an imbalance in the composition of oral bacteria; this instigates microbial dysbiosis, along with failed resolution of the chronic destructive inflammation. The objectives of this study were to identify microbial signatures for health and chronic periodontitis at the genus level and to propose a model of dysbiosis, including the calculation of bacterial ratios. Published sequencing data obtained from several different studies (196 subgingival samples from patients with chronic periodontitis and 422 subgingival samples from healthy subjects) were pooled and subjected to a new microbiota analysis using the same Visualization and Analysis of Microbial Population Structures (VAMPS) pipeline, to identify microbiota specific to health and disease. Microbiota were visualized using CoNet and Cytoscape. Dysbiosis ratios, defined as the percentage of genera associated with disease relative to the percentage of genera associated with health, were calculated to distinguish disease from health. Correlations between the proposed dysbiosis ratio and the periodontal pocket depth were tested with a different set of data obtained from a recent study, to confirm the relevance of the ratio as a potential indicator of dysbiosis. Beta diversity showed significant clustering of periodontitis-associated microbiota, at the genus level, according to the clinical status and independent of the methods used. Specific genera (Veillonella, Neisseria, Rothia, Corynebacterium, and Actinomyces) were highly prevalent (>95%) in health, while other genera (Eubacterium, Campylobacter, Treponema, and Tannerella) were associated with chronic periodontitis. The calculation of dysbiosis ratios based on the relative abundance of the genera found in health versus periodontitis was tested. Nonperiodontitis samples were significantly identifiable by low ratios, compared to chronic periodontitis samples. When applied to a subgingival sample set with well-defined clinical data, the method showed a strong correlation between the dysbiosis ratio, as well as a simplified ratio (Porphyromonas, Treponema, and Tannerella to Rothia and Corynebacterium), and pocket depth. Microbial analysis of chronic periodontitis can be correlated with the pocket depth through specific signatures for microbial dysbiosis.IMPORTANCE Defining microbiota typical of oral health or chronic periodontitis is difficult. The evaluation of periodontal disease is currently based on probing of the periodontal pocket. However, the status of pockets "on the mend" or sulci at risk of periodontitis cannot be addressed solely through pocket depth measurements or current microbiological tests available for practitioners. Thus, a more specific microbiological measure of dysbiosis could help in future diagnoses of periodontitis. In this work, data from different studies were pooled, to improve the accuracy of the results. However, analysis of multiple species from different studies intensified the bacterial network and complicated the search for reproducible microbial signatures. Despite the use of different methods in each study, investigation of the microbiota at the genus level showed that some genera were prevalent (up to 95% of the samples) in health or disease, allowing the calculation of bacterial ratios (i.e., dysbiosis ratios). The correlation between the proposed ratios and the periodontal pocket depth was tested, which confirmed the link between dysbiosis ratios and the severity of the disease. The results of this work are promising, but longitudinal studies will be required to improve the ratios and to define the microbial signatures of the disease, which will allow monitoring of periodontal pocket recovery and, conceivably, determination of the potential risk of periodontitis among healthy patients.

Roseburia spp.: a marker of health?

The genus Roseburia consists of obligate Gram-positive anaerobic bacteria that are slightly curved, rod-shaped and motile by means of multiple subterminal flagella. It includes five species: Roseburia intestinalis, R. hominis, R. inulinivorans, R. faecis and R. cecicola. Gut Roseburia spp. metabolize dietary components that stimulate their proliferation and metabolic activities. They are part of commensal bacteria producing short-chain fatty acids, especially butyrate, affecting colonic motility, immunity maintenance and anti-inflammatory properties. Modification in Roseburia spp. representation may affect various metabolic pathways and is associated with several diseases (including irritable bowel syndrome, obesity, Type 2 diabetes, nervous system conditions and allergies). Roseburia spp. could also serve as biomarkers for symptomatic pathologies (e.g., gallstone formation) or as probiotics for restoration of beneficial flora.